Embodiments relate to a light emitting device, a light emitting device package, and a lighting system.
Light emitting diodes (LEDs) are semiconductor light emitting devices that convert current into light.
A wavelength of light emitted from such an LED depends on a semiconductor material used for manufacturing the LED. This is done because the wavelength of the emitted light depends on a band-gap of the semiconductor material, which refers to an energy difference between valence band electrons and conduction band electrodes.
As brightness of LEDs has gradually increased in recent years, the LEDs are being used as light sources for displays, vehicles, and illuminations. Also, LEDs emitting white light having superior efficiency may be realized by using a fluorescent substance or combining LEDs having various colors.